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Hi all, we're reaching the last steps on our featherweight robot Turntable and we've been totally unable to find a suitable LED or suchlike to act as a safety light on our 18V system. A quick Google has suggested various linear vintage reduction devices but I imagine that wouldn't really be suitable for this kind of thing.

Does anyone have a suggestion for a solution or suitable light?

Also if anyone can advise the strength of Fuse needed for an 18V system powering two drill motors on TZ85A's with 10 AWG wires, I'd appreciate it. I'm not sure if we should use 40A, as that's the limit of the wires, or 80-85A as that's the limit of the ESC!

I use these now in all my bots. Plug right into the receiver on a spare channel and turn on when the receiver turns on. Just chop any lights you don't need (I tend to only use one) and insulate any cut wires.

I thought the whole deal with the safety light was that it had to be connected over all the circuitry of your robot. Like if your Rx blows up but power is still flowing to other parts, it doesn't really tell you that the robot is still powered on. For my LED I just use a normal red 1.8V LED and a resistor in series for this reason.

Think its preferred to be wired directly into the circuit, but via the RX is still acceptable. As regards to a 18v circuit, I've got three LEDs in series. So each bulb is getting a fraction of the 18v so they don't blow.

The rules (rule 6.4) simply state that the light must come on when the link is inserted. As I run my machines off a BEC in the main power circuit, it comes on when the link is inserted. I've never had an issue running this method.

Technically, that could also happen with a hardwired solution (the wires to the LEDs being cut by a spinner for example) and I think that is the crux here, is the only acceptable power light solution something that is hardwired into the main circuitry of the robot as opposed to a pluggable solution, such as plugging a LED into the receiver?

Having done both in the past, I am inclined to say that a hardwired solution is preferable because the receiver can be damaged and not provide power to the LED channel but still allow the other channels to work (although personally, I've never seen that happen) and having a light on the main circuit tells you exactly that, the main circuit is live.

When the LED rule was first brought in there was a 1000 reply thread on the topic (I'm not lying, it's probably still there). Keep it simple, link goes into robot, light comes on, link comes out, light goes out. Nice and simple. How your achieve this isn't prescribed. There are better and worse ways but that's up to you.

For Team Deaths new machine, the active light is on a seperate source of power (for sake of not having a multitude of resistors) - but it goes through the same link as every other component in the machine before it ends up at the LED. So it'll still be a true indication of the bots ability to cause surprises on approach. Unless an opponent manage to snap the LED cable and nothing else, but the way it is wired, you should have to destroy a lot of things to get in there, and you'd almost certainly knock out another set of wires anyway.